Sunday, May 28

The road ahead

When I wrote my Movin' on up in February, I speculated that I might reach position #40 on the probable-prime (PRP) production-score leaderboard by August. I'm a couple of months ahead of the game:

I had back then anticipated generating in the time interval (to reach #40) some 27 new PRPs worth about .01 each. Instead, I have to date discovered only 15 new PRPs, but 11 of these are greater than 83000 decimal digits — worth about .02 each, thus the time discrepancy. The road ahead is pictured above. I have taken it as far as #28, Norbert Schneider. I know Norbert because he is searching for the same type of PRPs (Leyland primes) that have created the bulk of my production score, but he has been doing this for much longer. He searches for other types of primes as well and is quite active, so when I take another leaderboard snapshot in a year or two I somewhat expect his score to have kept pace with mine. The caveat being that the algorithm that creates the production score is not the simple additive procedure I have made it out to be and Norbert's score may be weighed down by the larger number of smaller primes that he has over time accumulated.